|any of numerous small brownish insectivorous bats of the genus Pipistrellus, occurring in most parts of the world: family Vespertilionidae|
|[C18: via French from Italian pipistrello, from Latin vespertīliō a bat, from vesper evening, because of its nocturnal habits]|
any of about 68 species belonging to the vesper bat family (Vespertilionidae). Pipistrelles are found in almost all parts of the world. They are grayish, brown, reddish, or black bats that are about 3.5-10 cm (1.4-4 inches) long, not including the tail, which may be 2.5-6 cm (1-2.4 inches) long.
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